Lucicutia grandis ( Giesbrecht, 1895 )

Markhaseva, E. L. & Ferrari, Frank D., 2005, New species of Lucicutia and taxonomic status of L. grandis (Copepoda, Calanoida, Lucicutiidae), Journal of Natural History 39 (15), pp. 1077-1100 : 1078-1084

publication ID	https://doi.org/ 10.1080/00222930400005740
persistent identifier	https://treatment.plazi.org/id/DA7B8794-FF93-FFC5-FE1C-FC468E7C8D21
treatment provided by	Felipe
scientific name	Lucicutia grandis ( Giesbrecht, 1895 )
status

Treatment

Lucicutia grandis ( Giesbrecht, 1895)

( Figures 1 View Figure 1 , 2 View Figure 2 )

Leuckartia grandis Giesbrecht 1895, p 258 , Plate 4, Figure 2 View Figure 2 .

Lucicutia grandis: Giesbrecht and Schmeil 1898, p 111 ; Hulsemann 1966, p 724, Figure 101; S. Ali-Khan and J. Ali-Khan 1982, p 268 –269, Figures 19–22.

Lucicutia challengeri Sewell 1932, p 290 –294, Figure 95; 1947, p 174.

Female

Total length 4.7–4.9 mm. Prosome 1.7–1.8 times longer than urosome. Cephalosome with pointed protrusions ( Figure 1A–C View Figure 1 ). Rostrum not divergent; rami closely spaced ( Figure 1D View Figure 1 ). Genital double-somite with conical plug ( Figure 1G, I, J View Figure 1 ). Anal somite nearly as long as two preceding somites together ( Figures 1E–J View Figure 1 ), with dorsal side strongly swollen ( Figure 1G–J View Figure 1 ). Caudal rami in dorsal view 1.0–1.3 times longer than anal somite and about five times longer than wide ( Figure 1E, F View Figure 1 ). Antennule exceeding body length by distal segment. Medial seta at exopodal segment 2 of P5 attenuate, thin at tip ( Figure 1K View Figure 1 ).

Male

Total length 4.1–4.6 mm. Prosome 1.65–1.80 times longer than urosome. Cephalosome with pointed protrusions ( Figure 2A View Figure 2 ). Rostrum not divergent, with closely spaced rami. Antennule exceeding body length by about two segments; of 21 articulated segments, segment 18 longest ( Figure 2D, E View Figure 2 ). The first exopodal segment of right P5 slightly shorter than segment 2 ( Figure 2H, J, K View Figure 2 ); endopodal segment 2 without surface spinulation ( Figure 2I View Figure 2 ). Medial distal part of basipod of left P5 with saw-like, toothed margin; exopodal segment 3 oval-rounded ( Figure 2F, G View Figure 2 ).

Remarks

The following combination of characters distinguishes the females of L. grandis from L. bradyana : anal somite swollen dorsally in lateral view (swollen ventrally in L. bradyana ; Figure 4D–F View Figure 4 ); genital-double somite with conical plug (rounded in L. bradyana ; Figure 4D–F View Figure 4 ); medial seta at the exopodal segment 2 of female P5 attenuate and thin at the tip (in L. bradyana this seta robust; Figure 4G–I View Figure 4 ); rostral rami closely spaced (divergent in L. bradyana ; Figure 4A–C View Figure 4 ). Lucicutia grandis differs from L. wolfendeni as follows: large anal somite swollen dorsally (anal somite of L. wolfendeni only slightly swollen dorsally; Figure 8D–F View Figure 8 ); genital double-somite of L. grandis with a conical plug ( L. wolfendeni with an elongate-oval plug; Figure 8D–F View Figure 8 ); caudal rami of L. grandis are 1.0–1.3 times longer than anal somite (2.9–3.1 times longer than anal somite of L. wolfendeni ; Figure 8C, D View Figure 8 ); rostral rami of L. wolfendeni are divergent ( Figure 8G–I View Figure 8 ) and not closely spaced as in L. grandis . Females of L. grandis are smaller than L. wolfendeni and L. bradyana . Total length of L. grandis females studied here is 4.7–4.9 mm; published records of females: 5.54 mm after Sewell (1932); 4.4–6.5 mm after Hulsemann (1966); and 3.8–4.0 mm after Ali-Khan and Ali-Khan (1982). However, larger sizes given by Hulsemann (1966) are for specimens identified here as L. bradyana (see below).

The left P5 basipod of males of L. grandis which is not elongate medially-distally ( Figure 2F, G View Figure 2 ) differs from both L. bradyana , in which there is an elongate medial-distal projection with varying number of terminal teeth ( Figures 6B, D View Figure 6 , 7A 2 –C 2), and L. wolfendeni in which the projection is present but less pronounced ( Figure 9F View Figure 9 ). The third exopodal segment of the left P5 of L. grandis is oval-rounded, while for L. bradyana it is elongate-oval and for L. wolfendeni it is elongate-triangular ( Figures 2F, G View Figure 2 , 6B, D View Figure 6 , 7A 2 –C 2, 9F). The second endopodal segment of the right P5 of L. grandis is unarmed ( Figure 2I, K View Figure 2 ), while that of L. bradyana is densely hirsute. The inner margin of the right basipod of L. grandis has a small tooth-like indentation which differs from the distinct, proximal-facing lobe of L. wolfendeni ( Figure 9G View Figure 9 ). Sizes of males of L. grandis here are smaller than the male studied by Giesbrecht (1895), 6.0 mm, and larger than those of Ali-Khan and Ali-Khan (1982), 3.0– 3.6 mm, but similar to those recorded by Sewell (1932), 3.9–4.60 mm, and Hulsemann (1966), 3.9–4.9 mm.

Lucicutia grandis was described originally by Giesbrecht (1895) from a single damaged male from the Eastern Tropical Pacific (1 ° N, 83 ° W); only the P5 was illustrated. Because the description of species is based on an incompletely illustrated male, the identification of L. grandis has remained problematical. In a revision of the genus, Hulsemann (1966, p 719) mentioned ‘‘None of the many subsequent records of Lucicutia grandis seems to be this species. Sewell (1932, p 289) proposed to establish for these records a new species, L. wolfendeni ’’. In the same publication several nominal species of Lucicutia were placed in synonymy with L. grandis , including L. bradyana Cleve, 1904 . That is a decision we reconsider here. Lucicutia bradyana Cleve, 1904 is recognized as a separate species based on the differences between the two groups of specimens enumerated above. However, we accept Hulsemann’s conclusion that L. challengeri Sewell, 1932 is a junior synonym of L. grandis . Sewell (1932, Text-Figure 95h, j) illustrates the female P5 with a thin medial seta on the second exopodal segment and the shape of male P5 typical for L. grandis observed here.

Distribution

Lucicutia grandis is found in the eastern tropical Pacific Ocean at 1 ° N, 83 9 W ( Giesbrecht 1895) and in the Indian Ocean north from 10 ° 07 9 S. Specimens identified as L. grandis by Hulsemann (1966, p 717) from Anton Bruun stations 134, 348A, 349B, 353A, 354A, and 355C are L. bradyana . However, specimens from stations 108, 112, 330, 332, and 342 (see Figure 2K View Figure 2 ) are L. grandis ( Hulsemann 1966, p 717) . Specimens from Discovery cruise III station 5251, Anton Bruun station 328 and John Murray Expedition station 76 were not reexamined here. Based on records from the existing literature ( Sewell 1932; Hulsemann 1966; Ali-Khan and Ali-Khan 1982) and data here, L. grandis is distributed in the northern part of the Indian Ocean, in the Arabian Sea and in the Bay of Bengal. The southernmost finding is 10 ° 07 9 S ( Hulsemann 1966); the northernmost is 24 ° 09 9, 64 ° 27 9 N ( Ali-Khan and Ali-Khan 1982). Records from the Atlantic Ocean are ambiguous and date from Wolfenden (1911). However, Wolfenden’s Figure 60 for L. grandis appears to be an illustration of L. bradyana . Björnberg (1973, p 343) recorded L. grandis from the southeastern Pacific Ocean between 07 ° S and 58 ° S without providing descriptions or illustrations.